Re: Dynamically setting struct values from hash map
On Thursday, 12 May 2016 at 21:01:06 UTC, Adam D. Ruppe wrote: foreach(member; __traits(allMembers, YourStruct)) if(member in yourhash) __traits(getMember, your_object, member) = to!right_type(yourhash[member]); basically, it is a bit more complex to filter out inappropriate fields and such, but that's the idea. Check out the sample chapter of my book https://www.packtpub.com/application-development/d-cookbook to see more, you can get the reflection chapter free on that site. That's wonderful Adam, thank you! I actually had your book previously bookmarked - I should probably buy it :-)
Re: Dynamically setting struct values from hash map
On Thursday, 12 May 2016 at 20:52:46 UTC, Andrew Chapman wrote: I have seen the "allMembers" method from the traits module that can give me the names of the struct fields, but I am unsure if it's even possible to set the struct values using variable/dynamic names. Yes. You can't loop over the hash and set values on the struct, since looping a hash is a run time operation, but you can loop over struct members. So, the trick is to loop over the struct members (a compile-time operation) and set them (converting type with `std.conv.to` if necessary) if the value is in the hash. foreach(member; __traits(allMembers, YourStruct)) if(member in yourhash) __traits(getMember, your_object, member) = to!right_type(yourhash[member]); basically, it is a bit more complex to filter out inappropriate fields and such, but that's the idea. Check out the sample chapter of my book https://www.packtpub.com/application-development/d-cookbook to see more, you can get the reflection chapter free on that site.
Dynamically setting struct values from hash map
Hi guys, apologies for the silly question, but I come from the
world of dynamic languages and I'm wondering if it's possible to
set struct values basic on dynamic variables?
e.g.
struct Person {
string firstName;
string lastName;
}
void main() {
string[string] map;
map["firstName"] = "Homer";
map["lastName"] = "Simpson";
}
Is it possible to iterate through the hash map and set the struct
values using the key/value pairs?
Something like this:
e.g.
Person p1;
foreach(key,val; map) {
p1[key] = val;
}
The problem I'm trying to solve is that I'm wanting to write a
generic "model" class that can read a record from a database and
populate a known struct from the database values. I have seen
the "allMembers" method from the traits module that can give me
the names of the struct fields, but I am unsure if it's even
possible to set the struct values using variable/dynamic names.
Any help will be greatly appreciated!
Cheers,
Andrew.
